Negative carrier structure for photographic enlargers



E. C. ROGERS Dec. 23, 1941,

NEGATIVE CARRIER STRUQTURE F'OR PHOTOGRAPHIC ENLARGERS Filed Feb. 17,1940 2 Sheets-Sheet 1 fzmoazaPaazag, .2?

ATTORNEYS Dec. 23, 1941 E. c. ROGERS I NEGATIVE CARRIER 2,266,908STRUCTURE FOR PHOTOGRAPHIC ENLARGERS Filed Feb. 17, 1940 INVENTOR. fix0406. P062195, BY

. ATTORNEYS.

Patented Dec. 23, 1941 UNITED STATES PATENT OFFICE NEGATIVE CARRIERSTRUCTURE FOR PHOTOGRAPHIC ENLARGERS 16 Claims.

It is the object of my invention to improve the construction ofphotographic enlargers. Particularly, it is my object to improve thenegative carrier and its associated structure in an enlarger of the typeshown in my co-pending application Serial No. 277,886, filed June 7,1939; to improve the convenience with which the negatives of strips orrolls of film may be enlarged, and at the same time to provide for theenlargement of negatives which are on individual pieces of film. Theseindividual negatives are usually cut from a strip or roll, and areconveniently referred to as cutfilms.

The accompanying drawings illustrate my invention: Fig. 1 is a sideelevation of an enlarger, with parts shown in section; Fig. 2 is a frontelevation of the parts of the enlarger of Fig. 1 adjacent the negativecarrier; Fig. 3 is a vertical section taken on the line 3-3 of Fig. 1and showing generally the same parts as Fig. 2, on an enlarged scale;Fig. 4 is a horizontal section taken on the line 44 of Fig. 3; Fig. 5 isa side elevation of the structure of Fig. 3; Fig. 6 is a verticalsection taken on the line 6--6 of Fig. 3; Fig. 7 is an exploded view ofa negative carrier in its arrangement for use with a cut film; Fig. 8 isan exploded view of a negative carrier in its arrangement for use withstrip film carrying negatives of relatively small size; and Fig. 9 is anexploded view showing how a pair of glass plates may be used as anegative carrier in my enlarger.

The enlarger shown is Suitably supported by means including an arm 12..The end of the arm I2 is provided with a housing I5, which isconveniently part of the same casting with the arm I2. This housing I5is a shell which is open at both top and bottom, and tapers downwardly.Near its lower end, the housing I5 is provided with a transverse slot [6for receiving a negative carrier. Just above the transverse slot IS, thehousing [5 is preferably provided with an inwardly extending flange 18on which a suitable condensing lens l9, shown as a plano-convex lens,may rest. I consider this condensing lens very desirable; but it is notfundamentally essential.

The upper end of the housing I5 is provided with a bell enlargement 20for receiving the lower end of a lamp-housing 2| which carries a lampsocket in which a suitable depending lamp bulb 23 is mounted. The upperend of the bulbhousing 2| is provided with a central opening for a lampcord (not shown) which supplies current to the lamp bulb 23, and withventilating openings 25 to permit the outflow of air that is heated bythat lamp bulb 23.

' Below the transverse slot l 6 which receives the threads 34.

. may be mounted inside of the sleeve.

negative carrier, the housing [5 is provided with a flat lower end 30. Abarrel 33 is fastened to that lower end of the housing 15, which barrelis provided, at least at its lower end, with internal An externallythreaded sleeve 35 may be screwed into the internally threaded barrel33, with either end of the sleeve 35 uppermost. The sleeve 35 isprovided at both ends with a pair of threaded longitudinally extendingholes 36, conveniently near the opposite ends of a diameter, forreceiving threaded pins 31 to provide a convenient finger hold foradjusting the sleeve 35 in the barrel 33; and th pins 31 are put in theholes 36 in whichever end of the sleeve 35 is to be downward.

One end of the sleeve 35 is provided with an inwardly extending flange38, in which an objective lens 39 of long focal length may be mounted,with that lens projecting below the flange 38 when the flange 38 is atthe bottom end of th sleeve. If an objective lens of short focal lengthis desired, however, the sleeve 35 may be turned end for end, so thatthe flange 38 is at its upper end, and a short-focus lens (not shown) Ineither case, the objective lens is desirably provided with an adjustablediaphragm, adjustable by the usual circumferentially movable knurledcollar 43 by which the size of its light-transmitting opening may beadjusted, in known manner.

The slot 16 for receiving a negative carrier extends through the frontwall 45 and through all but a small section at the rear of each of theside walls 46 of the housing l5. Below the slot I6, each side-wall 46carries on its outer surface a guide 41 for a negative-plate (to bedescribed later). Such guides 41 extend upwardly from the portions ofthe side-walls 46 below the slot l5 and project a short distance abovethe lower surface of the slot IS. The portions of such guides 41 whichare above such lower surfaces of the slot l6 have inner surfaces 'alinedwith the outer surfaces of the side-walls 45; so that the lower surfaceof the slot [6 is flat over the entire width of the enlarger casingbetween the walls 46, with those guide standing above such lower surfaceat the side edges thereof. Each side wall 46, below the guides 41, isprovided with a threaded hole to receive the clamp screw 48 of a guidefinger 49 which is slotted for adjustment toward and away from the innerwall of the slot IS. The two guide fingers 49 extend upwardly well pastthe lower surface of the slot l6 and are adapted to be engaged by therearward edge of a strip film El held by a negative carrier in the slot16.

The negative carrier to be received in the slot l and particularlyadapted for use with negatives on a strip of film comprises a pair ofplates 65 and 52.

The plate 66, adapted in this use to be the lower or the two plates andto underlie the negative so that it forms a negative-support is a flatplate with a central film-masking opening, and is adapted to lie on thelower surface of the slot it between the guides 47. Its thickness isslightly greater than the height of the guides 47 above such lowersurface, so that the plane of its upper surfac is wholly unobstructed.The negativesupporting plate 50 is normally stationary in use, but ismade removable for interchange with others which have differentfilm-masking openings. As will be seen in Fig. 8, the plate 65 isgenerally rectangular in shape, with a forwardly extending curvedportion I5 and a rearwardly extending portion 7 l.

The plate 52 of the negative carrier, adapted in this use with stripfilm to be the upper plate and to overlie the film, has a central flatsection which is of the same size as the plate 60, and

at its side and front edges is bent upwardly to form upstanding wallshigher than the opening of the slot it, so that they overlap the wallsof the housing I5 above such slot I6. From the upper edges of suchupstanding walls at the side edges, the material of the plate 52 extendsoutwardly above and past the guide fingers 49, then downwardly to theplane or the central section of the plate 52, and then outwardly to formlifting flanges 5 The plate 52 thus has a central section, withadownwardly open channel 63 secured to each of its side edges and with aflange 64 extending laterally from the channel. The upstanding walls atthe sides and front of the central section serve to close the upperportion of the slot It at its open sides and front to prevent the escapeof light. Each pair of plates 60 and 62 are provided with centralopenings of a size adapted to mask a negative of one particular size.The plates are desirably provided in sets of several pairs of plates 56and 52, with the different pairs provided respectively with centralopenings for different standard sizes of negatives which it may bedesired to enlarge.

The side walls of the upper plate 62 not only close the opensides of theslot it, but also serve to locate such plate 52 laterally in properposition in the slot and in relation to the lower plate 55, the lowerplate 55 being positioned by the guides 41. Both plates are furtherlocated, by engagement at their rear edges with the inner wall of theslot it. a film between them and against the lower surface of the slot15 by springs 53, respectively mounted on the side walls 45 of thehousing I5 just above the slot [5, which press downwardly on the upperfaces of the channels 63.

Adjacent to the rear Wall of the enlarger casing [5 and behind the slotHi there is a shaft 50 extending transversely through the casing I5. Ateach end of this shaft to there is a lifting arm 5! which is fixed tothe shaft 55 and extends forward therefrom in position to lie beneaththe flange 51] of a negative carrier plate 62. An operating arm 52extends upwardly from at least one, and desirably from both, ends of theshaft 50, and is also fixed on the shaft 55, so that operation of anoperating arm 52 will cause both lifting arms 5! to engage the undersurfaces of the flanges 5'5 and lift the plate "52 away from its Theplates are held against engagement with the film 6|, to permit anydesired manipulation of such film 6 I.

The movement of the arms 52 is desirably limited. For this purpose, eachside wall of the housing l5, just above the shaft 50, carries a lug 55extending outwardly to the inner edge of its associated arm 52, and suchlug 55 has spaced extensions 56 at its end, which lie in the path of thearm 52 to limit its movement. The lugs 55 may also serve to support thesprings 53 which press downwardly against the negative carrier plates.To this end, a second lug 5? lies beneath each of the lugs 55 and isspaced slightly therefrom. The springs 53 are bent to form a pair ofspaced shoulders 58 to engage the edges of the lug 55, and between thoseshoulders 58 the spring is of irregular configuration, as by having adownward oifset 59; so that the spring may be pressed into the slotbetween the two lugs, and

will be held firmly therebetween by the springpressure of the shoulders58 against the lug 55, and of the offset 59 against the lug 51. Thepresence of the operating arm 52 at the outer end of the lugs 55 and 51prevents the spring from slipping outwardly from its position betweenthe lugs 55 and 51.

In the operation of this structure with the negative holder described,one of the operating arms 52 is pressed rearwardly to cause both liftingarms 5| to lift against the flanges 54 of the upper plate 62 of thenegative carrier, to lift the u per plate 62 against the pressure of thesprings 53, to the position shown in Fig. 6. The strip film 6! is theninserted from the front, and is moved rearward until it engages the twoguide fingers 49, which are adjusted to guide the film 6| to a positionin which the center line of its negatives will be alined with the centerof the openings in the negative carrier plates 65 and 62. With theplates thus separated, the strip film 6| may next be moved lengthwise tobring the desired negative into alinement with the openings of thenegative carrier. The arm 52 is then released, and the springs 53 pressthe upper plate 62 downwardly against the upper surface of the film 6!,to hold such film 5| flat and in proper position for focusing andprinting. When suitable focusing and printing operations have beenperformed with the selected negative, another negative on the same stripof film may be moved into position for printing by again pressing anoperating arm 52 rearwardly to separate the plates to permit such him tobe moved longitudinally to bring such other negativeinto registry withthe openings in the negative carrier plates. The handle 52 is thenreleased, and the second selected negative is ready for printing.

When it is desired "to enlarge a cut-film negative, the arrangement ofparts shown in Fig. 7 is used. The negative '13 to be enlarged is placedon the upper surface of the central section of a plate 62 which has anopening of the size desired forsu'ch negative 13. A plate 60 having asimilarly sized opening is laid on top of the film l3, andby'i-tswe'ight holds the negative 7'3 in the desired position. A third,plate 50, with an opening of the same or a larger size "than that ofthe plates 55 and 62 selected for holding the negative '13, is placed ind e enlarger between the guides 47, so that a surface 'is provided bythe upper surface of such plate 630" above the upper ends of the guides41. The assembled plates .65 and '52 with the negative 73 then insertedin the slot 1 6 of the enlarger on top of the plate 60, and s held downagainst the plate 5i) by the springs 53 so that the negative 13 is heldin proper position normal to the axis of the enlarger. Because thecentral section of the plate 62 is of the same size as the plate 60,such plate 60 has a fairly accurate fit between the upstanding Walls ofthe plate 62 and is thus held from lateral movement except in a rearwarddirection. When the combined plates 60 and 62 are inserted in theenlarger, the shoulders at the sides of the rearward extensions H of theplates 60 and 62 engage the rear wall of the slot l6, so that the plate60 is then held from lateral movement in any direction.

If desired, my enlarger may also be used with a negative carrier such asthat shown in Fig. 9. This negative carrier consists of two plates ofglass 15 and 16. The lower plate 15 is of the same size and shape as therectangular portion of a plate 60 so that it fits between the guides 4'1and against the short portions 45' of the side Walls 45 at the rear ofthe slot I6. The upper glass plate I6 is desirably of the same length asthe overall length of a plate 62 so that its ends will overlie thelifting arms During the use of this glass negative carrier, the guidefingers 49 are adjusted to their extreme rearward position, so they willnot interfere with the glass plate 16. If desired, an upper plate 62 ofthe form of negative carrier shown in Fig. 8 and having an opening of asuitable size may be inserted on top of such glass plate "I6, so thatthe side-walls of such plate 62 will close the slot [6. The plate 62 mayalso serve as a mask, but desirably has a relatively large opening, andany desired masking is obtained by the use of a mask applied to theupper surface of the glass plate 16.

The operation of the glass plate l5-'l6 negative carrier for theenlargement of negatives from a film strip will be substantially thesame as with the use of the plates 60 and 62 in the arrangement of Fig.8 and as shown in Fig. 3, for the lifting fingers 5| will underlie theupper glass plate 16 so that that glass plate may be lifted away fromthe lower glass plate 15 by pressing rearwardly on one or the other ofthe operating arms 52.

I claim as my invention:

1. In a photographic enlarger, walls forming I a slot for the receptionof a negative carrier having separable upper and lower plates, one ofsaid plates having extensions projecting outwardly beyond opposite onesof said walls, a pivotally mounted arm adjacent each of said oppositewalls on axes parallel with the plane of said extended plate with thefree ends of said arms respectively in position to engage said plateextensions, said arms being interconnected for simultaneous operation,and an operating member for said arms to move them to separate theextended plate from its associated plate.

2. In a photographic enlarger, walls forming a slot for the reception ofa negative carrier having separable upper and lower plates, one of saidplates having extensions projecting outwardly beyond opposite ones ofsaid walls, a pivotally mounted arm adjacent each of said opposite wallson axes parallel with the plane of said extended plate with the freeends of said arms respectively in position to engage said plateextensions, said arms being interconnected for simultaneous operation,an operating member for said arms to move them to separate the extendedplate from its associated plate, and spring-means on said enlargeracting on said plates oppositely to the separation action of said arms.

3. In a photographic enlarger, walls forming a slot for the reception ofa negative carrier having separable upper and lower plates, one of saidplates having extensions projecting outwardly beyond opposite ones ofsaid walls, said extended plate being offset away from the associatedplate adjacent each of said opposite walls, a pivotally mounted armadjacent each of said opposite walls on axes parallel with the plane ofsaid extended plate with the free ends of said arms respectively inposition to engage said plate extensions, said arms being interconnectedfor simultaneous operations, an operating member for said arms to movethem to separate the extended plate from its associated plate, andadjustable guide fingers mounted adjacent to said opposite walls andextending across the plane of separation of said plates and into theclearance space provided by said ofiset.

4. A photographic enlarger comprising a housing having walls forming aslot for the reception of a negative carrier, a negative-carrier plateadapted to be received in said slot, a second negative-carrier plateadapted to lie against said first plate and having side walls extendingaway from the plane of separation of said plates and slidably engagingthe side of the enlarger to position said side-walled plate in theenlarger, said enlarger sides being parallel, oppositely and outwardlyextending flanges on said side walls, and means on said enlarger forengaging said flanges and operable to separate said plates.

5. A photographic enlarger comprising a housing having walls forming aslot for the reception of a negative holder, a negative holder includinga movable plate which has a face adapted to engage a negative, verticalside faces on said enlarger adjacent said slot, said slot being ofsufiicient Width to permit considerable movement of said plate while inposition in the slot, side walls on said movable plate extending acrossthe clearance space in said slot and slidably engaging said side facesto close said space against escape of light and to position said movableplate, said movable plate being spring-pressed to urge said face towardthe face of a normally stationary negative-support to hold a negativetherebetween, means for moving said plate away from said negativesupport, and an adjustable negative guide at the plane of separationbetween said plate and negative-support.

6. A photographic enlarger comprising a housing having walls forming aslot for the reception of a negative carrier, a negative-carrier plateadapted to be received in said slot, a second negative-carrier plateadapted to lie against said first plate, oppositely and outwardlyextending stretches on said second plate which are ofiset from saidplane of plate separation, and negative guides carried by the enlargerand adjustable in said plane of separation and which extend across saidplane of plate separation into the clearance space provided by theoffsetting of said stretches.

7. A negative carrier for a photographic enlarger which has walls cutthrough by a slot for the reception of the negative carrier, comprisinga pair of plates of materially less thickness than the width of saidslot, one of said plates having side walls positioned to lie against theenlarger walls to close the slot against escape of light and to permitplate separation.

8. In a photographic enlarger, wall forming a slot for the reception ofa negative carrierhaving separable upper and lower plates, said upperplate extending beyond the enlarger walls, means mounted on the enlargerhaving portions arrangedto engage the extending portions of the upperplate for lifting the upper plate while it is in position in theenlarger, a pair of lugs extending laterally from opposite side wallsoi? the enlarger housing, each pair of lugs being spaced apart to formagroove therebetween, a sprin supported in each oi'said grooves andarranged to press the negative-carrier plates together, said liftingmeans having also a portion lying across the ends of the lugs of eachpair in position to prevent said springs from moving outwardly out ofengagement with said lugs.

9. The combination defined in claim 8, with the addition that theportions of said litfing means which lie at the ends of the lugs aremovable, said lugs being adapted to interengage said lifting meansportions to limit the movement thereof.

10. The combination defined in claim 8, with the addition that theportions of said lifting means which lie at the ends of the lugs aremovable, and stop means limiting the movement of said portions.

ll. In a photographic enlarger, walls forming a slot for the receptionof a negative carrier having separable upper and lower plates, means forlifting the upper plate while it is in position in the enlarger, saidlifting means comprising lifting fingers adapted to interengage one ofsaid negative-carrier plates on opposite sides of the exposing openingtherein and pivotally mounted on a common axis, and means forsimultaneously moving said fingers to move the interengaged plate awayfrom its associated plate to permit the movement of a negativetherebetween.

12. In combination, a photographic enlarger having walls cut to form aslot for the reception of a negative carrier, a negative carriertherefor, said negative carrier comprising a pair of plates, the firstofsaid plates having. upstanding walls to slidably engage the walls ofthe enlarger adjacent said slot to position said plate in the enlarger,the second plate being adapted to be received within andpositioned bysaid upstanding Walls whereby the assembly is adapted to receive a cutnegative between the plates and to be movable as a unit, and means onthe enlarger for independently positioning said second plate in positionon the opposite side of said first plate from its upstanding- Walls,whereby the plane of separation between the plates is unobstructed forreceiving a. strip negative.

13. In combination, a photographic enlarger, a negative carriertherefor, said negative carrier comprising a pair of plates, the firstof said plates having means co-operating with parts of the enlarger forpositioning it therein, said means also being adapted to position thesecond of said plates with respect to said first plate when the secondplate is on one side of the first plate, and independent means on theenlarger for positioning the second plate when it is used on the otherside of the first plate.

14. The combination defined in claim 12 with the addition of a thirdplate adapted to be received by said independent positioning means andto support said walled plate.

15. A photographic enlarger, comprising a housing having a slot for thereception of a negative carrier, a negative carrier including a pair ofplates one of which is adapted to lie against one side surface of saidslot, guide means to position said plate in the slot, the second of saidplates being adapted to lie against said first plate and to be spacedfrom the opposite side surface of said slot, walls on said second plateadapted to slidably engage the casing walls adjacent to said oppositeside surface of said slot to position the plate with respect thereto andto close the slotagainst the escape of light While permitting separationof said plates, said plates having alined negative-exposing openingstherethrough.

16. A photographic enlarger as defined in claim 15 with the addition ofa third plate adapted to be received between said walls and to bepositioned thereby on said second plate for holding a cut negativethereon, said third plate also having a negative-exposing opening.

ELWOOD C. ROGERS.

